Polaris Dawn has just made history again.
SpaceX’s private four-person astronaut crew conducted the world’s first commercial spacewalk high above Earth on Thursday (Sept. 12) during the third day of a five-day journey into Earth orbit.
“SpaceX, we still have a lot of work to do at home, but from here it looks like a perfect world,” said Polaris Dawn commander Jared Isaacman, the American billionaire who funded the mission, as he looked down at Earth, standing mostly outside the Dragon hatch.
SpaceX launched the four astronauts – Isaacman, pilot Scott “Kidd” Poteet, and mission specialists Sarah Gillis and Anna Menon (both of SpaceX) – into orbit on Tuesday (Sept. 10) aboard a Falcon 9 rocket. The rocket lifted off from the historic Launch Complex 39A at NASA’s Kennedy Space Center, the same launch pad that launched Apollo 11, the first manned mission to the moon.
Fifteen hours later, the crew made space history for the first time when they reached an altitude of 875 miles (1,400.7 kilometers) – higher than any manned mission since the Apollo program half a century ago. Another NASA mission, Gemini 11, previously held the altitude record for a manned spacecraft in Earth orbit at 855 miles (1,373 kilometers).
But Polaris Dawn did not stop here.
After reaching the record altitude, the mission’s Crew Dragon Resilience spacecraft descended to 458 miles (737 km) at its highest point. Once there, Resilience was depressurized and Isaacman and Sarah Gillis exited the room one at a time, with Isaacman coming out at approximately 6:48 a.m. EDT (10:48 a.m. GMT) and Gillis at 7:04 a.m. EDT (11:04 a.m. GMT).
The spacewalk began at 6:12 a.m. EDT (10:12 a.m. GMT), nearly four hours later than originally announced, and was expected to last about two hours. During the spacewalk, both Isaacman and Gillis performed a series of spacesuit mobility tests while SpaceX captured stunning live images of the two astronauts standing up, with most of their bodies outside the spacecraft.
The Dragon space shuttle hatch was closed at around 7:14 a.m. EDT (11:14 a.m. GMT) as SpaceX began restoring pressure to the spacecraft. According to SpaceX, the entire spacewalk lasted one hour and 46 minutes, from 6:12 a.m. EDT (10:12 a.m. GMT) to 7:58 a.m. EDT (11:58 a.m. GMT).
“Phew! Can you smell that? Space,” Isaacman said after the hatch was closed and the capsule began to pressurize. “Great job by everyone at SpaceX for making this possible.”
The Polaris Dawn crew includes Isaacman, who funded and led the mission, mission specialists Gillis and Menon, and pilot Poteet, a former U.S. Air Force lieutenant colonel.
The spacewalk (also known as extravehicular activity or EVA) was made possible by several special pieces of hardware developed for Polaris Dawn.
The crew wore new EVA suits designed by SpaceX that are lightweight and flexible, yet provide protection from the harsh, unforgiving conditions of Earth orbit. A SpaceX spacesuit engineer described them as “an armor made of cloth.”
One of Polaris Dawn’s main goals was to test the suits that SpaceX plans to use on a number of future missions, both in Earth orbit and further into space. “We recognize that it could be in 10 iterations and a number of evolutions of the suit, but that one day someone could wear a version of it that could walk on Mars,” Isaacman said Aug. 26. “And it feels like a great honor again to have the opportunity to test it on this flight.”
Polaris Dawn also features a heavily modified Crew Dragon spacecraft. The crew was able to exit the Resilience capsule for their spacewalk thanks to a special hatch designed specifically for this mission, known as the “Skywalker,” which replaced Dragon’s typical ISS docking station.
The Skywalker’s hatch is equipped with a ladder and hand and foot grips that the Polaris Dawn astronauts can hold on to while maneuvering around the outside of the Dragon capsule.
Polaris Dawn is also testing a new communications system that uses lasers to connect to SpaceX’s Starlink satellites, a mega-constellation that provides broadband internet around the world. The system “has the potential to open up a whole new way of communicating, not just for Dragon, but for (…) Starships or other satellites or telescopes out there,” Isaacman said at a press conference on August 19.
In addition to testing the new SpaceX hardware and spacesuits, the four Polaris Dawn astronauts have conducted 36 different science experiments provided by 31 different institutions. These experiments will be conducted throughout the mission, including some that will provide data to NASA’s Human Research Program and help scientists better understand how the human body responds to spaceflight.
Just like the spacesuit tests, these experiments are designed to help carry human exploration of the cosmos into the future. “Every mission, whether the crew is made up of commercial or NASA astronauts, provides an important opportunity to advance our knowledge of how spaceflight affects human health,” Jancy McPhee, NASA’s deputy chief scientist for human research, said in a statement. “The information collected by Polaris Dawn will provide us with important insights that will help NASA plan deeper spaceflights to the Moon and Mars.”
These experiments range from testing wearable devices that collect biometric data to attempts to alleviate motion sickness to testing eye health in microgravity. Polaris Dawn has also traveled through parts of Earth’s Van Allen radiation belt, offering the opportunity to better understand how this radiation affects the human body.
Polaris Dawn is the second private SpaceX mission funded by Isaacman. The first, Inspiration4, launched in September 2021 and was the first crewed orbital mission without professional astronauts. This mission was also operated using Resilience.
Both Inspiration4 and Polaris Dawn raised money for St. Jude Children’s Research Hospital in Memphis, Tennessee. Inspiration 4 raised a total of $250 million for St. Jude.
Polaris Dawn is scheduled to return to Earth on day six and parachute into one of several possible ocean landing zones off the coast of Florida. A recovery ship will then pick up the Resilience spacecraft and crew, completing one of the most ambitious manned space missions in decades.